Unloading mechanism for compressors



40 known construction, the air is admitted to Patented Apr. `13,192.6.

UNITED' STATES FRED D; HOLDSWOBTH, OIE' MACHINERY COMPANY, CORPORATION 0F MASSACHUSETTS.

UNLOADING.' MECHNISM FOR COMPRESSORS.

lApplication led March A14:, 1917. Serial No. 154,811.

To all whom t may d o'ncem: v f

Be it known that I, FRED D.' HOLDS- WORTH, a citizen of the United States,`re siding at Claremont, in the county of-Sullivan and State of New Hampshire, have invented'. certain new and useful Improvements in Unloading Mechanism forCompressors, of which the following is a full, clear, and exact specification. Y

My invention relates to compressors. 1

It has for its objectto load or unload a lcompressor of the plate valve type in an improved manner. A further object. of my invention is to provide improved means whereby such a compressor may be loaded or unloaded through control of its inlet valve or valves. A still further object of my invention is to provide improved means controlling the loading and unloading of such a compressor, especially adapted to use with an automatic jcontrol system wherein the loading or unloading means is automatically operated. A

In the accompanying drawings, I have shown for purposes of illustration one embodiment which my invention may assume in practice. i i

Fig. 1 is a partial longitudinal sectional' view through one end of a compressor cylinder equipped with my improvement. Y

-Fig. 2 is a transverse sectional view taken on line 2-2 of Fig. 1. j

Fig. 3 isa detail sectional view of the coinplete`mechanism taken on line A3---3 of Fig. o

In this illustrative construction, it will be noted that a compressor having" a cylinder 1 and a piston 2 movable therein, is provided with a cylinder head 3. As in a well the cylinder 1 through communicating inlet passages 4 in the cylinder and lhead and a series of valve ports 5 opening into the cylinder and controlled by a plate valve, herein shown to comprise a jlurality of resilient or fingered, norm'ally closed', plate valve members 6 moving between the ported valve" seat 7 and curved guards 8 preferably formed on a single plate 9 having slots 104 therein leading into the cylinder. The air is also 4discharged Afrom this cylinder 1 through a series of ports 11 controlled by a similar series of plat'e valve members 12 operating between the valve seat 13 and a slotted guard CLAREMQNT; NEW HAMPSHIRE', AssIeNoR To suLrivN plate 14,`lthe air passing out through these y ports into discharge passages 15, separated from the passages 4 by a wall 16 in the head. As the specific. construction or type of the'discharge valves, however, does not 'enter into my present invention, the same need I iot here-be more-specifically described.

In my improvement, it will be noted that disposed adjacent the inlet valves 6, Iis a valve operating means adapted to engage one or more, and preferably each, `of the resilient fingers of the valve members, and'iaise the i vsame from their normal engagement with their seats in`;such a manner as to open com- `m`unication from the inlet passages 4 to the cylinder 1 and thus unload thecompressor. This means in the form shown herein, comprises a member 17 pivoted at 18 at a point within the hea-d and having a series or gang of projections, lugs or fingers 19 thereon adapted -toengage 'with the `sev'eral inlet valve members .6 at a point adjacent their i ends and lift the same from their'seats and force the same against the curved guards 8 therefor, which are provided on the guard plate9. As shown','this member 17 presents a narrow surface to the fiow of fluid, guides the fingers so that the latter do not strike the valve seats or other velements ofthe valve or compressor and is normally heldy inoperal to as the valve members return to-their seats.

It. will also be noted that I have provided a surface 21 on the member 17 disposed over a small cylinder 22, preferably formed in the head 3, and that in this cylinder I have provided a piston 23, preferablyhaving a boss 24 on its upper end, so that when the cylinder 22 is'supplied with lpressure fiuid from a suitable source, such as a 'pressure fluid connection 25, this boss 24 may engage the surface 21 on the member 17 and force that member upward against its spring 2O to 'raise' the valve members 6 from their seats and thereby unload the compressor.

In the use of my improvement, itwillbe noted that the member 17 may, as shown in Fig. 3, be pivoted to a bracket or plate 26 which may be clamped to the cylinder head by one of the bolts 27 which are used to clamp the guard plate 9 upon the valve members 6 and clamp both of the same to the cylinder head, thus producing an exceedingly simple and cheap construction. It will also be noted that the supply of air to the piston 23 may be controlled by any means adapting the device to use in an automatic system, as for instance a pilot or unloader valve 28, which is in turn connected tothe receiver (not shown) through a pipe connection 29, and is adapted to admit pressure to thc pipe 25 and thereby unload the compressor when the pressure rises above a predetermined amount in the receiver, and to exhaust the pressure in this pipe 25 when the receiver pressure falls below a predetermined amount. As this pilot valve is, however, of a well known construction, known in the art as the Judson pilot valve, a detailed description of the same is believed to be unneeesf sary.

It will be noted that as a result of my improved construction, a compressor having one or more inlet valves ofthe plate type may be unloaded whenever desired and without injury to the valves, by simply causing the elevation of one or more of the members 17, and that as soon as the force elevating the latter is removed, the compressor will be loaded. By applying the force adapted to open the valves adjacent the free ends there-- of a much wider opening is effected, as they are caused to bend around their curved guard members and conform to the shape of the latter much more closely than were the con- .tact at a lower point; and thereby a clear opening of much greater size is provided. lt will be seen that the free end of' the valve, beyond the contact of the fingers, is tangent to the curve of the guard, so that vthe nearer to the end of the valve that contact'occurs, the greater the clear opening. It will also be evident that the mechanism by which the unloading of the compressor is brought about may bc very cheaply produced and readily inserted within a cylinder head and appliedto a standard compressor, and'that, if dcsired, the same may be automatically operated in such a manner as to adapt it to use in connection with an automatically controlled system of any suitable type. Obviously, however, the member 17 may, in certain formsof the invention, be operated by any desired means. These and other advantages of my improved construction will, however, be apparent to those skilled in the art.

lVhile I have in this application specmcally described one embodiment which my invention may assume in practice, it is of course to be understood that the invention is not limited thereto but may be modilied and embodied in various other forms without departing from its spirit, it being my intenhaving a cylinder having a port communieating therewith anda valve controlling said port and flexing about a transverse line in opening, of an element adapted to engage said valve at a point remote from said transverse line and to flex it into open position.

2. The combination with a compressor whichhas a cylinder having a port communicating therewith and a valve controlling said port and flexing about a transverse line in opening, of an arcuately movable element adapted to engage said valve at a point remote from said transverse line and to flex it into open position.

The combination with a 'compressor which has a cylinder having a port communicating therewith and a valve having a fixed end and a freely movable end controlling said port, of unloading means ad'acent said freevend for moving' said vfree ent. l. The combination with a compressor which has a cylinder having a port communicating therewith and a valve member having a lived end and a freely movable end and controlling said port, of' unloadingmeans comprising a finger adapted to contact with said free end and a finger actuating member mounted on said cylinder adjacent the free end of said valve member.

5. The combination with a compressor which has a cylinder and a port communieating therewith and a valve member having a fxedend and a freely movable end and controlling said port, of unloading means" comprising a linger adapted to contact with said tree end an d a finger actuating plunger mounted on said cylinder adjacent the free end of said valve member; v

6. rlhe combination with a compressor' which has a cylinder having a port communicating therewith and a valve member having a fixed end and a Jfreely movable end and controlling said port, of unloading means coniprising a member adapted to raise the freeend .of said valve member from its seat, guiding means for said second named member, and actuatingmeans for said second named member.

7, The combination with a compressor which has a cylinder having a port communicating therewith and a valve member having a fixed end and a freelymovable end and controlling said port, of unloading means comprising a member adapte-d to raise the free end of' said valve member from its seat, guiding means for said second named member, and actuating means for said seec-nd named member, said guiding means extending longitudinally'of said valve member.

' j 9. The combination"withna means comprising a member ada ted. ltofraise .1 the free end of'said valve mem er from its.. seat, pivoted guiding means for said second named member, andA actuating means `for said second-named member."

compressor I which has `a cylinder having-aportcommunicating therewith Vand a valve member having a :fixed end and a freely -movable end and controlling Said port, of unloading means comprising a member adapted to raise 'the free endl of saidvalve member from'its seat, guiding means for said second named Y member, and actuatingmeans for said Secf comprising amember of greater-width than thickness andpresentingi a narrovvvsurfaceg inder and arranged 1n said head, a ,ported ond. named member, said guiding means l in thepath of the luid flow.

10. The combination with a compressor which lias'a cylinder` having a plurality ofports communicating therewith and valve .means controlling` said 4ports comprising a plurality of elastic valve members each.v having a fixedv end and a freely movableend, cfa. gang of fingers adapted to contact with said valve members`v adjacent thcirfreely movable ends tohold the valve members inoperative, and gui-ding means for Asaid gang.

'11. The combination' with .a compressor which has a cylinder having a plurality of ports communicating'therewith and valve means controlling said portsy comprisingA vf,

plurality of elastic valve members each hav-` ing a fixed end and a freely movable end, of a simultaneously movable gang of fingers ers .adapted to contact with said valve mem adjacent .their freely movable lends to hold 'the valve ,members inoperative, guiding means for said gang, and means for normally holding` Vsaid lgangin an inoperative position.

12. The combination'with a compressor which'comprises a cylinder having a cylinder'head,za ported valve seat formed in saidv cylinder head, a ported guard plate having a curved guard thereon, and a plurality of plate valves fixe-d to said head'at one end and having their' opposite ends normally vengageable with said seatv and iieziible into en.

gagement with said curved guards, of normally inoperative means carried in said head for flexing said valve members against said curved guards. f

13. As an article of manufacture,in combination, a cylinder head having `a ported valve seat formed therein, a curved guard disposed over aport in said seat, a plate "valve member attachedat one end to said seat and between the latter and said guard unloading' mechanism including a pivoted member carried in said head engageable with .the free end of said4 valve member to raise the latter from its seat, and a single-means for attaching said guard, said valve and said member'to said head.

- 14. As an article ofmanufacture, in lcombination, a cylinder head .having a ported valve seat .formed therein, a curved guard disposed 'over a Vport in said seat, a plate valve member attached at one end to said seat and between 'the latter and saidguard, a `pivoted member carried in said head .en-

Oageablewith the `free end of said Valve inein f lier to raise the latter from its' seat, al cover platefor ysaid cylinder head l a .cylinder formedY insaid cover'v plate, an fapistonreciprocable in sadclinderand operative to member to effect open- 'Y actuate said pivote ing. of said valve. v

15. The combinationwith a compressor lwhich h as a cylinder, a cylinder head, a ported valve seat communicating 'with said cylguard plate o ening into said cylindervand ed valve seat communicating with said cylf inder andlar'ranged in said head, a ported guardfplate oening into said cylinder, and a plura it of exible valve'members clamped at one en l'between' said guard plate and seat resting onsaid seat, of means carried in said and having their opposite jends normally head and engageable withy the free ends-of said valve members for lifting the same from their seats, cooperatin means normally rendering said last mentioned means inoperative, and fluid pressure means for operating said first mentioned means.

" 17. The. combination lwith a compressor comprising a cylinder having a head, a

ported valve seat communicating With said cylinder and arranged in said head, a ported llO guard plate opening into said cylinder, and s a plurality of flexible valve members clamped at one end between said guard plate and seat'.

and having their opposite ends normally resting on said seat. of' a member pivotally mounted in said head having a plurality of fingersv thereon engageable With certain o1? said valve members to lift the same from their seats, resilient means normally rendering said member inoperative, -a 'cooperating cylinder, a pist-on vmovable in said cylinder and engageabl'e with said member, and automatic controlling mechanism controlled 'by the receiver pressure for supplying and exhausting pressure fiuid beneath said piston.

18. The combination with a compressor which comprises a cylinder having an inlet valve comprising an elastic valve member having a fixed end and a freely movable end, of a member pivoted at one end and havingI means for engaging and moving the free end of said valve.

lf). The combination with a compressor which comprises a cylinder having an inlet valve con'iprising an elastic valve member having a fixed end and a freely movable end, of a member pivoted at one end and having means for engaging and moving the free end of said valve, and a spring engaging the free end of saidunloading member for normally holding the same inoperative.

20. The combination with a compressor which comprises a cylinder having anl inlet valve comprising an elastic valve member having a fixed end and a freely movable end, of a member pivoted at one end and having means for engaging and moving the free end of said valve, a second cylinder, and a piston in said last named cylinder loosely engaging said unloading member for operating thel same.

21. The combination with a compressor which comprises a cylinder having an inlet valve comprising an elastic valve member having a lixed end and a freely movable end, of a member pivoted at one end and having means for engaging and moving the free end of said valve, a spring engaging the l.free end of said unloading member for normally holding the same inoperative, a second cylinder, and a. piston in said .last named cylinder loosely engaging said unloading member for operating the same.

22. The combination with a compressor which comprises a cylinder landan inlet alve therein comprising an elastic valve member having a fixed end and a freely movable end, of a member pivoted at its end adjacentthe fixed end of said valve, and having means for engaging and moving the free end of said valve.

23. The combination with a compressor which comprises a cylinder, a. ported valve seat, an elastic valve cooperating with said seat, and a curved guard cooperating with said valve, of a member having means for engaging and operating said valve, a support upon which said member is pivoted at one end, and means for clamping said support, one end of said valve, and one end of said guard to said valve seat.

24. The combination With a compressor which comprises a cylinder, a valve seat having a plurality of ports and a valve member fixed at one end and having a plurality of elastic fingers each cooperating vith one of said ports in saidvalveseat, of a member pivoted at one end and having a rasees/i therein comprising an elastic valve member having a fixed end and a freely movable end, of means operable from the exterior of the cylinder for engaging the free end of said valve and controlling the operation thereof.

Q6. rhe combinationv With a compresso-r which comprises a cylinder and a valve therein comprising an elastic valve member lravin g a fixed endY and a freely movable end, of means operable 'from the exterior of the cylinder for engaging the afree end of said valve and lifting the same from its seat.

27. As an article'of manufacture, in combination, a cylinder head comprising an open ended chamber and a cover therefor, ports traversing a Wall of said chamber, valve means cooperating With said ports, means for unseating said valve megns, and means for actuating said unseating means comprising fluid voperated means carried by said cover and disposed Wholly Within the exterior limits of said cylinder head.

28. As an article of manufacture, a cylinder head comprising, in combination, an-

open ended chamber and a cover therefor7 one ivall of said openended chamber being traversed by at least one port, a valve xed at one end and overlying said port and flexible to permit flow through said port,

means for opening said valve including a piveted member overlying said valve, and

operating means for said pivoted member including a cylinder carried by said cover and projecting into said chamber, and a piston reciprocable in a path lying Wholly` Within the limits of said head."

29. The combination "with a compress-or which comprises a cylinder having a port communicating therewith, a valve control'- ling said port and flexing upon opening about a line extending transversely thereof, and a guard disposed at the side of said valve opposite said port and limiting the opening of said valve, the side of said guard adjacent said' valve being curved and abeing tangent to said valve at said transverse line whereby said valve on opening progressively flexes into contact With saidguard, of an element adapted to engage said valve at a point remote from the transverse line and flex it into open position.

30. The combination with a compressor which comprises a cylinder having an elongated port communicating therewith, an elongated valve overlying said port and having free and fixed ends and flexible to open said port, of an elongatedmember pivoted adjacent the fixed end of said valve for arcuate movement. in a plane perpendicular to the plane of said valve when the latter is closel,A and means for actuating able in substantially the same direction as said pvoted member to open suidwalve.. the ow of fluid through said port, of an 31'. The combination with a compressor element adapted to engage said Valve and 10 which has a cylinder having a. port comiex the same into open position. 5 municating therewith and a exible Valve In testimony whereof 1 aix my signature.

cont-rolling said port and exing to open thev latter said val-ve having an end freely mov- FRED D. HOLDSWORTH. 

